The present invention relates in general to hopper-type containers, and more particularly, to forming and handling a slurry and solutions in hopper-type railroad cars.
For certain materials, storage and discharge thereof in slurry form has many advantages over storage and discharge thereof in dry form. For the sake of convenience, a generic term "liquefied mass" will be used to include both a slurry and a solution. However, no limitation on the scope of the invention is intended by this terminology, and such is being employed only for the convenience thereof. In some instances, transportation in slurry form may also be advantageous over transportation in dry form. Thus, it is quite common for many materials to be stored and discharged in slurry form.
Generally, a slurry is formed in a container by initially loading material in dry form into a container, then liquefying that dry material by pumping a liquid into the container and mixing that liquid with the material while sometimes adding air in the late stages of agitation.
If the liquid is not thoroughly mixed with the initially dry material, the slurry has non-uniform properties, such as density, consistency, and the like. Such a non-uniform slurry causes many problems in handling and discharge of that slurry material. While high pressure liquid introduction into the container may help somewhat in the mixing steps, this method is not entirely satisfactory.
The inventor is aware of slurry unloading systems, such as that disclosed in U.S. Pat. Nos. 3,512,842 and 3,378,387. In U.S. Pat. No. 3,512,842, air is discharged into the bulk material. However, in systems such as that disclosed in the just-mentioned patent, the air discharge apparatus is simply a plurality of pipes extending upwardly into a hopper. There is no device capable of discharging gas at or very near the bottom of the hopper, and in a manner which efficiently mixes and fluidizes the material. Merely discharging air into the body of such material is not sufficient to adequately fluidize that material, or to fluidize the material near that location on the hopper used as an inlet for liquid and/or an exit for the slurry or solution. Furthermore, there is no provision in U.S. Pat. No. 3,512,842 for coupling the liquid and air lines to promote efficient fluid handling to and from the hopper.
The device disclosed in U.S. Pat. No. 3,512,842 thus is susceptible to compacting of the dry product, which may result in product lumps into which liquid will not penetrate. Such lumps are detrimental to a slurry or solution handling method.
Thus, the inventor is not aware of any means or method for transforming into slurry form an initially dry product which is to be stored and handled in slurry form in a hopper-type container, and particularly in a hopper-type railroad car, which is thorough enough to completely assure the formation of a slurry which is consistent and thoroughly liquefied. The present invention is embodied in a means and method for insuring the formation of a consistent and thoroughly liquefied slurry or solution.